Baby weight

Once your little bundle of joy has entered the world, it’s perfectly natural to be fascinated by your baby’s weight. Afterall, your baby’s weight is one of the first things people will ask you about your newborn, once you’ve told them whether you have had a boy or a girl!

Like adults, babies come in all different shapes and sizes, but as your baby grows, their weight is an important sign they are feeding well and a positive indicator that your little one is happy and healthy. It’s important to keep an eye on your baby’s weight gain or loss, but that often means parents can find themselves fretting about whether or not their baby is too big or too small.

This concern is totally understandable, but remember, your public health nurse will perform regular check-ups to monitor your little one’s weight and will also measure the length and head size of your baby. They are there to support you if your baby loses a large amount of weight or doesn't regain their birth weight within two weeks, so they will want to know all about how feeding is going. If you are breastfeeding, they may even ask to see you feeding your little one, just to ensure your baby’s feeding and growing as they should.

Newborn weight loss

Every child follows a growth pattern from birth - and usually the first thing they do is lose weight! This is more common in breastfed babies. Babies can lose up to 10% of their birth weight in the first few days but should have gained this again by around day 10. It's normal for your baby to lose a bit of weight during their first few days after birth; this is because they are born with a little extra fluid, which they swiftly get rid of!

Newborns also tend to lose weight because it can take your baby a little while to get used to drinking milk, and if you’re breastfeeding, your body also has to get used to producing milk, too.

How often should you weigh your baby?

It’s very easy to become a little obsessive about your baby’s weight, but after the first two weeks of birth, you really don’t need to weigh your baby that often. Your public health nurse will advise you on this.

How much weight should my baby gain?

In the first few weeks, your baby will probably gain about 175g to 225g (6oz to 8oz) a week in weight. By about six months, they will probably have doubled their birth weight, and after this their weight gain will gradually slow down.

The centile charts used to measure growth are just guidelines. So while your baby’s weight should normally stay within this range, don’t be worried if they have the occasional blip. These may be caused by growth spurts, illness, difficulty adjusting to solids or simply burning up more calories as they start to crawl. If you have any concerns about your baby’s growth, speak to your healthcare professional.